Certain astronomical observations are most readily made with a detector array that has been cooled to within a fraction of 1 degree Kelvin. In order to provide and maintain so low a temperature, adiabatic demagnetization refrigeration systems have been developed that can provide such temperatures. They entail the use of salts having suitably large magnetic moments which are subjected to the cooling effects of the adiabatic demagnetization process employed, the details of which are not part of the subject matter of this application but which are further discussed in U.S. Pat. No. 6,959,554, the contents of which are hereby incorporated by reference. This salt is housed in a cylinder called a “salt pill,” which is located in a bore contained within a magnet that is part of the ADR.